The present invention relates to a crimp contact device and more particularly to, for example, a crimp contact device for crimping a contact metal firmly against a core wire of a covered electric wire.
FIGS. 1A and 1B show an example of a crimp contact device of this type (refer to Patent Document 1, for example). As is shown in FIG. 1A, a core wire 191 of an electric wire 190 is crimped by a core wire crimping portion 130 which lies at a substantially central portion of the crimp contact device 110 to thereby be attached to a crimp contact device 110. In a technique disclosed in Patent Document 1, as is shown in FIG. 1B, a bell-mouth portion 133, which is formed so that an end portion thereof is opened to be oriented outwards, is provided so as to prevent the core wire 191 from being damaged to be disconnected by an end portion of the core wire crimping portion 130 in such a state that the core wire 191 is crimped by the core wire crimping portion 130. In FIG. 1B, an area P1 is an area where the core wire 191 is compressed so as to be completely crimped, and an area P2 is an area where the core wire 191 is not compressed.
[Patent Document 1] Japanese Patent Publication No. 2003-168536 A
Incidentally, as has been described above, in the crimp contact device 110 to which the electric wire 190 is attached via the bell-mouth portion 130 provided thereon, there has sometimes happened a situation in which the securing force is insufficient at the portion where the core wire 191 of the electric wire is crimped by the core wire crimping portion 130. As a result of studies carried out, it has been found that a reduction in securing force is possible to occur due to stress concentration at an end portion Y (a boundary portion between the core wire crimping portion 130 and the bell-mouth portion 133) of the core wire crimping portion 130 where the electric wire 190 (the core wire 191) is crimped and that particularly, in the case of an electric wire (a core wire) which is thin in diameter, there is a fear that the securing force becomes insufficient. In addition, as is shown in FIG. 1C, since stress varies drastically at an area S1, there has been a case where the core wire 191 is disconnected.